SAN DIEGO (AP) — A Mexico-born Harvard University student has returned to the United States after being stuck for months in his native country when he crossed the border without permission.

The U.S. Citizenship and Immigration Service initially declared that Dario Guerrero Meneses effectively deported himself when he crossed the border with his mother as she sought alternative cancer treatments. She died in August.

Guerrero, 21, who was brought into the U.S. illegally at age 2, crossed through the San Ysidro Port of Entry on Tuesday on his way to Long Beach, California, to reunite with his father and two siblings.

“I feel very fortunate for all the help I’ve received from all the people who supported me,” Guerrero told The Associated Press.

He had been granted a visa in Tijuana on Monday.

Guerrero plans to return to Harvard next year.

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